Bupleurum longiradiatum

Bupleurum longiradiatum belongs to the carrot family, Apiaceae. It is a perennial, which means it lives for years. Its native range spans parts of eastern Asia. These include China, Japan, and Siberia. It is not native to Britain or Ireland. Wild plants grow in woods and patches of shrubs. They also grow on dry slopes without too much exposure. Records show it grows in mountains across Japan.

The plant grows about 3.3 feet (1 metre) tall. The sources give no width for a full-grown plant. Nor do they describe its leaves in detail. It blooms from August to October. Its seeds ripen in those same months. Each flower has both male and female organs. Insects move pollen between flowers. The plant can also set seed with its own pollen. The evidence gives no fruit shape or colour.

Plants For A Future lists sand, loam, and clay as suitable soils. Its account for this species favours moist soil that drains well. It lists soil that is slightly acid, neutral, or slightly alkaline. The same account gives mixed advice on light. It says the plant cannot grow in shade. Yet it also lists woods with patches of light shade. It lists garden beds as another place to grow it. How well it copes with British cold remains unclear. The source gives no tested heat or cold limit. Its native range suggests it may grow outdoors in Britain. Separate notes on how to grow it use the genus's general needs.

The source explains how to grow this species from seed under glass. It advises sowing in spring at about 15°C. Seeds may take two to eight weeks to sprout in these conditions. Move each young plant to its own pot when large enough to handle. Keep them under glass for their first winter. Plant out in late spring or early summer, after expected frosts. The source suggests spring division, but this method lacks proof.

Records note a food use for young cooked leaves. But this does not mean they are safe to eat. Plants For A Future also lists this species as toxic. It warns against using it in place of chai hu. Records note uses of the seeds to treat several ailments. They do not prove that home treatment works or is safe. The toxic warning outweighs the listed food and medicinal ratings. The source records no other uses and flags no weed risk. The evidence gives no pest or disease details for this species.